1. Field of the Invention
This invention relates to monoclonal antibodies useful in the detection of the white pine blister rust fungus Cronartium ribicola.
2. Background of the Invention
White pine blister rust is a disease which infects five-needle pines such as eastern white pine, western white pine and sugar pine. The fungus was inadvertently introduced into western North America at Vancouver, Canada in 1910. The fungus has five different spore stages on two unrelated hosts, namely white pines and Ribes. The basidiospores are produced on Ribes in the Fall, and are transported by wind to pine foliage where they germinate. The mycelium of the fungus then grows down the needle until it reaches the bark causing the canker which eventually kills the tree. Although some larger and older trees can survive, infected young trees almost inevitably die.
Because western white pine trees have a high stumpage value and are resistant to root rot disease, a program has been developed in western Canada to select and screen blister rust resistant trees for planting seed orchards with the ultimate purpose of reforestation with resistant trees. Candidate trees, which are canker free, are identified, and seeds are collected from such trees. Two year old seedlings grown from the seeds are inoculated with the Cronartium ribicola fungus, usually in late August. In the following spring, the needle infection intensity is recorded. One hundred percent of high spotted seedlings develop cankers and are culled. Low spotted seedlings are kept for observation for as long as seven years, whereby some resistance characteristics such as no cankers or slow canker growth or needle shed are observed. Trees with such resistance mechanisms are eventually used in seed orchards.
Obviously, such a selection program based on phenotypic criteria is very time consuming and expensive, and may not be precise. Accordingly, a need exists for a method which facilitates the selection and screening of disease resistant trees.